This invention pertains to laminate, glass fiber non-woven fabric for base material of laminate and a method of producing the glass fiber non-woven fabric.
Glass non-woven fabric has been conventionally used for base material of electrically insulating laminate. The laminate has been produced by impregnating the base material with thermosetting resin and forming them under heat and under pressure. The glass non-woven fabric before impregnated with thermosetting resin has glass fibers bound by binder to each other.
The binder has been conventionally produced as disclosed in Japanese patent Application Publication No. 39474/1977, for example. In this Publication, 1,2 epoxide compound having more than two oxilane functions included in a molecule and having epoxy equivalent of 170 through 1000 is reacted with water-soluble polyamine compound having more than at least one active hydrogen bound with nitrogen atom at a ratio of more than 1/4 of the active hydrogen in the water-soluble polyamine compound relative to one oxylane function in the epoxide compound. The thus obtained product has an acid added thereto to induce water-soluble or water-dispersed amine-epoxide acid salt which is quickly cured under heat.
The disclosed binder has glass transition temperature of about 95.degree. C. and is produced by using 40 weight parts of solvent in order to improve a control of reaction progress.
However, thermosetting resin laminate having base material of glass fiber non-woven fabric produced by binding glass fibers to each other by the conventional binder tends to have contraction in size produced while the laminate is processed under heat.
In addition thereto, a large quantity of solvent has to be used for producing the conventional binder.